Currently, there are several known apparatuses which allow to launch balls for sports practice purposes, but generally they are apparatuses for launching tennis balls or baseballs.
It should be noted that there are considerable differences in terms of size, weight, and weight/volume ratio among the balls used in different sports.
Said differences make it impossible to use an apparatus devised to launch tennis balls to launch footballs instead, or to adapt it for this purpose.
Among the different existing apparatuses the most interesting are those which are easy to transport, and which can be easily operated in any point, for instance within a football field.
Examples of similar easily transported apparatuses are disclosed in the patents U.S. Pat. No. 3,662,729, GB 2 118 443 and U.S. Pat. No. 4,774,928.
In particular the patent U.S. Pat. No. 4,774,928 discloses an apparatus for launching tennis balls for training purposes comprising a tank for pressurised air, a launch tube whose section substantially corresponds to that of a tennis ball, and which has an open end for launching the ball and an end connected to the tank by means of a quick opening device, which allows rapidly to discharge the air contained in the tank through the tube, thereby causing the launching of the ball.
However, known apparatuses are not suitable for launching footballs in the aforesaid manner. On one hand, they do not allow an effective launch of a football, which has very different weight and diameter compared to tennis balls. Moreover, apparatuses of this kind on one hand do not assure a repetitive launch of the ball, on the other hand do not allow to adjust launch velocity (at least, non in an easy and precise manner).